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Removing Duplicate Rows in a file
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DBIx::Class::Helper::Schema::LintContents(3pm) User Contributed Perl Documentation DBIx::Class::Helper::Schema::LintContents(3pm) NAME
DBIx::Class::Helper::Schema::LintContents - Check the data in your database match your constraints VERSION
version 2.013002 SYNOPSIS
package MyApp::Schema; use parent 'DBIx::Class::Schema'; __PACKAGE__->load_components('Helper::Schema::LintContents'); 1; And later, somewhere else: say "Incorrectly Null Users:"; for ($schema->null_check_source_auto('User')->all) { say '* ' . $_->id } say "Duplicate Users:"; my $duplicates = $schema->dup_check_source_auto('User'); for (keys %$duplicates) { say "Constraint: $_"; for ($duplicates->{$_}->all) { say '* ' . $_->id } } say "Users with invalid FK's:"; my $invalid_fks = $schema->fk_check_source_auto('User'); for (keys %$invalid_fks) { say "Rel: $_"; for ($invalid_fks->{$_}->all) { say '* ' . $_->id } } DESCRIPTION
Some people think that constraints make their databases slower. As silly as that is, I have been in a similar situation! I'm here to help you, dear developers! Basically this is a suite of methods that allow you to find violated "constraints." To be clear, the constraints I mean are the ones you tell DBIx::Class about, real constraints are fairly sure to be followed. METHODS
fk_check_source my $busted = $schema->fk_check_source( 'User', 'Group', { group_id => 'id' }, ); "fk_check_source" takes three arguments, the first is the from source moniker of a relationship. The second is the to source or source moniker of a relationship. The final argument is a hash reference representing the columns of the relationship. The return value is a resultset of the from source that do not have a corresponding to row. To be clear, the example given above would return a resultset of "User" rows that have a "group_id" that points to a "Group" that does not exist. fk_check_source_auto my $broken = $schema->fk_check_source_auto('User'); "fk_check_source_auto" takes a single argument: the source to check. It will check all the foreign key (that is, "belongs_to") relationships for missing... "foreign" rows. The return value will be a hashref where the keys are the relationship name and the values are resultsets of the respective violated relationship. dup_check_source my $smashed = $schema->fk_check_source( 'Group', ['id'] ); "dup_check_source" takes two arguments, the first is the source moniker to be checked. The second is an arrayref of columns that "should be" unique. The return value is a resultset of the source that duplicate the passed columns. So with the example above the resultset would return all groups that are "duplicates" of other groups based on "id". dup_check_source_auto my $ruined = $schema->dup_check_source_auto('Group'); "dup_check_source_auto" takes a single argument, which is the name of the resultsource in which to check for duplicates. It will return a hashref where they keys are the names of the unique constraints to be checked. The values will be resultsets of the respective duplicate rows. null_check_source my $blarg = $schema->null_check_source('Group', ['id']); "null_check_source" tales two arguments, the first is the name of the source to check. The second is an arrayref of columns that should contain no nulls. The return value is simply a resultset of rows that contain nulls where they shouldn't be. null_check_source_auto my $wrecked = $schema->null_check_source_auto('Group'); "null_check_source_auto" takes a single argument, which is the name of the resultsource in which to check for nulls. The return value is simply a resultset of rows that contain nulls where they shouldn't be. This method automatically uses the configured columns that have "is_nullable" set to false. AUTHOR
Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com> COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Arthur Axel "fREW" Schmidt. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. perl v5.14.2 2012-06-18 DBIx::Class::Helper::Schema::LintContents(3pm)
